1. Field of the Invention
The present invention pertains to fireplace heating and, more particularly, to a forced air circulation heating unit for installation entirely within a fireplace to increase heat obtained therefrom.
2. Discussion of the Prior Art
Fireplaces are used a great deal for heating and for the pleasant ambiance produced thereby; however, fireplaces are notorious for the wasted heat and fuel associated therewith in that not only does a great amount of heat created by the burning of fuel, such as wood, coal and the like, escape through the fireplace chimney but heat from the remainder of the house or building housing the fireplace is also exhausted through the fireplace chimney.
There have been attempts in the prior art to provide apparatus for increasing the efficiency of fireplace heating by drawing or forcing air through the fireplace to heat the air and return the heated air to the room, as exemplified by U.S. Pat. 2,642,859 to Brown. Such prior art apparatus, however, have suffered the disadvantages of being relatively bulky, expensive and difficult to install; and, further, such apparatus have invariably drawn air into the fireplace under a support for the burning fuel and forced the heated air out of the fireplace at a location vertically spaced from the indrawn air near the top of the fireplace. The circulation provided by such apparatus is limited, and the burning coals and ashes have tended to be massed at the rear of the apparatus tending to burn out the apparatus.
U.S. Pat. Nos. 2,828,078 to Snodgrass, 3,001,521 to Reilly and 3,240,206 to Schutt are exemplary of prior art appartus for supplying heated air from a fireplace by means of conduits forming parts of grates or incorporating baffles and adapted to have air blown therethrough. While these apparatus provide increased circulation of hot air, they are not as efficient in preserving fuel and obtaining maximum heat from fuel as is desirable.